Incubation time in sterility tests for pharmaceutical products

Throughout the evolution of sterility test methodology, different periods of incubation were adopted depending on both the type of microorganism to be detected and the employed inoculation methodology. Some official compendiums, such as Brazilian and Mexican pharmacopoeias, recommend different incubation periods, according to the inoculation methodology employed for the sterility test, whereas the United States Pharmacopeia, in its last edition, started to adopt an incubation period of 14 days, independently from the methodology employed. The aim of this work was the evaluation of the influence of the incubation time on the efficiency of different methodologies for sterility test, as well as the benefits that could be achieved with the incubation time extension. The experiments led to the conclusion that an incubation period of 14 days is enough for the detection of microbiological contaminants in pharmaceutical products submitted to sterility tests, independently from the methodology employed, what values the alteration introduced in the USP XXIV, to the detriment of other pharmacopoeias which maintain different periods of time in accordance with the inoculation method employed.